This just happened to me for the first time the other day. I had parked my car on the street, not in their parking lot, and the wheels of the cart just jammed up on me as I was leaving the store. So weird.

“Theft deterrent systems are becoming popular in many shopping centers. An electronic system works by locking one of the wheels, usually one on the front, when the cart is rolled out of a designated area. Each shopping cart is fitted with an electronic locking wheel, or ‘boot’. A transmitter with a thin wire is placed around the perimeter of the parking lot. The boot locks when the cart leaves the designated area. Often a line is painted in front of the broadcast range to warn customers that their cart will stop when rolled past the line. The locked wheel is usually unlocked with a portable electronic device carried by store staff called a “CartKey” that sends a signal to the boot, unlocking the wheel.”

I have seen this at one grocery store here in Memphis. I think they recently turned it off though because they re-paved the lot and the line wasn’t re-painted and the signs are gone. I’m sure enough people complained about it since this was the only store in Memphis that had it.

They use similar approach over here. Not exactly sure where the limit goes, but I know there is one and the wheels have these big clunky things on them – which doesn’t improve the already somewhat challenged steering of the carts…

the safeway by my old house in portland oregon had them except you could take one about two blocks away before they worked. i seen the same lady every 3 or 4 days push a cart the two blocks in front of my house. then it locked up and she got her groceries out of the cart and carried them the rest of the way home. sometimes there would be 4 or 5 carts just sitting on the sidewalk. when the beer cans piled up i would grab one of her carts and take them back to safeway to the bottle deposit refund machine.